Hyperthyroidism is the most common endocrine disease of older cats. The disease is accompanied by hyperactivity, weight loss and a palpable goiter. Although treatments are available, including anti-thyroid drugs, surgery or the use of radioactive iodine to destroy the glandular tissue, each of these interventions has limitations and side effects. Thus, an unfilled need exists for methods and compositions for reducing the risk of developing abnormal thyroid function and hyperthyroidism in cats.